Long story short, my brother was trying to figure out why my stereo's amp was not coming on, it ended out being the main fuze, that big bulky bullet shaped one. He was testing the power line by earthing it (creating a spark) to see if the line was carrying power to the amp.

The battery was not disconnected the whole time he did this. He blew one fuze that we could tell, since the sparking the car idles really low to stall point (its automatic) and the central and remote central locking doesn't work, the car is completely unlocked. Air conditioning works, radiator fan works, power windows and sunroof works. It takes alot longer to kick over when it starts, [usually its chuga chuga boom, now its chuga chuga chuga chuga chuga chuga chuga starts].
It can drive, but its dangerous when going slow. I have it booked in an auto electrician on wednesday. Ive checked both the engine bay and under the steering wheel at all the coloured fuzes that you can see if they're blown, but the big black ones i'd have no idea if they're blown or not. I know he's an idiot, but any technical advice would be very appreciative :)

If you're lucky you've just blown a bunch of fuses. If you're unlucky you've done some serious damage to the car electricals, and will probably require the auto elec to find the fault. Tell him to use a multimeter next time!

What model is your car?

Cheers for the help ol fart, ill give it a go and let you know, you're a legend mate :)

You cant really damage anything, everything is fused and bringing the batterys/earths potential down/up cant damage much.

You have just popped a fuse or fusable link. Check the main engine fuses, relays.

Edit: those big black ones are relays.

check the 2 fuses under the bonnet, in the yellow cradle. one will be blown.

I've checked and replaced them all. Same problem, the cars at the mechanic now. Ill post what the resolution to it is tomorrow (if its fixed).